var btns=document.getElementsByTagName("button");
var divs1=document.getElementsByClassName("rightbox1");
var divs2=document.getElementsByClassName("rightbox2");
var divs3=document.getElementsByClassName("rightbox3");
for(var i=0;i<btns.length;i++){
    btns[0].onclick=function(){
            if( this.innerHTML=="+"){
                divs1[0].style.display="block";
                this.innerHTML="-";
            }
            else{
                divs1[0].style.display="none";
                this.innerHTML="+";
            }   
    }
}


for(var i=0;i<btns.length;i++){
    btns[1].onclick=function(){
            if( btns[1].innerHTML=="-"){
                divs2[0].style.display="none";
                this.innerHTML="+";
            }
            else{
                this.innerHTML="-";
                divs2[0].style.display="block";       
          }          
    }
}

for(var i=0;i<btns.length;i++){
    btns[2].onclick=function(){
            if(this.innerHTML=="+"){
                divs3[0].style.display="block";
                this.innerHTML="-";
            }
            else{
                divs3[0].style.display="none";
                this.innerHTML="+";
            }    
    }
}